Device for manufacturing recycled carbon fibers, and method for manufacturing recycled carbon fibers

Abstract

The purpose of the present invention is to provide a manufacturing device and a manufacturing method that use carbon fiber reinforced plastic (CFRP) as a source material for the efficient, low-cost manufacture of recycled carbon fibers exhibiting excellent ease of handling. A device for manufacturing recycled carbon fibers is provided with: a dry distillation-carbonization furnace ( 101 ) having a box-shaped main body ( 105 ), a dry distillation-carbonization chamber ( 102 ) which accommodates CFRP ( 40 ), a combustion chamber ( 103 ) equipped with a burner ( 104 ), and a heating chamber ( 115 ) formed in the space between the main body ( 105 ) and the dry distillation-carbonization chamber ( 102 ); and a continuous furnace ( 26 ) that continuously heats the CFRP ( 25 ) after dry distillation and removes a portion of the fixed carbon. The device for manufacturing recycled carbon fibers of the present invention is characterized in that the dry distillation-carbonization furnace ( 101 ) is provided with a steam generator ( 105 ) and steam at a temperature of 100° C. or higher and 700° C. or lower is supplied to the dry distillation-carbonization chamber ( 102 ).

The invention claimed is: 
     
       1. A device for manufacturing recycled carbon fibers using carbon fiber reinforced plastic containing carbon fibers and a matrix component as a source material, comprising:
 a dry distillation-carbonization furnace that dry distils the carbon fiber reinforced plastic and converts a portion of the matrix component into fixed carbon to attach the fixed carbon to the surfaces of the carbon fibers, and is provided with a box-shaped main body, a dry distillation-carbonization chamber which is arranged in the inside of the main body and accommodates the carbon fiber reinforced plastic, a combustion chamber which is arranged in the lower part of the dry distillation-carbonization chamber and equipped with a burner, and a heating chamber formed in the space between the main body and the dry distillation-carbonization chamber; and 
 a continuous furnace that continuously heats the carbon fibers attached with the fixed carbon and removes a portion of the fixed carbon, and is provided with a mesh transportation part which transports the carbon fibers attached with the fixed carbon and an elongated tunnel-shaped heat treatment space, 
 wherein a steam generator is provided to the dry distillation-carbonization furnace and steam at 100° C. or higher and 700° C. or lower is supplied to the dry distillation-carbonization chamber. 
 
     
     
       2. The device for manufacturing recycled carbon fibers according to  claim 1 , wherein the steam generator supplies overheated steam at 500° C. or higher and 700° C. or lower to the dry distillation-carbonization chamber. 
     
     
       3. The device for manufacturing recycled carbon fibers according to  claim 2 , comprising:
 a plurality of the dry distillation-carbonization furnaces; 
 a branch pipe which supplies overheated steam from a steam generator of a first dry distillation-carbonization furnace to a dry distillation-carbonization chamber of a second dry distillation-carbonization furnace; and 
 a branch pipe which supplies overheated steam from a steam generator of the second dry distillation-carbonization furnace to a dry distillation-carbonization chamber of the first dry distillation-carbonization furnace, 
 wherein overheated steam generated in one dry distillation-carbonization furnace is supplied as a heat source to heat the dry distillation-carbonization chamber of the other dry distillation-carbonization furnace. 
 
     
     
       4. The device for manufacturing recycled carbon fibers according to  claim 1 , wherein the combustion chamber in the dry distillation-carbonization furnace and the regeneration space in the continuous furnace are connected through a heat resistant route, and
 exhaust heat from the dry distillation-carbonization furnace is supplied as a heat source of the continuous furnace. 
 
     
     
       5. A method for manufacturing recycled carbon fibers using carbon fiber reinforced plastic containing carbon fibers and a matrix component comprising:
 a dry distillation step of dry distilling the carbon fiber reinforced plastic while supplying steam at 100° C. or higher and 700° C. or lower by a dry distillation-carbonization furnace and converting a portion of the matrix component into fixed carbon to attach to the surfaces of the carbon fibers; and 
 a heat removal step of heating the carbon fibers attached with the fixed carbon by a continuous furnace having an elongated tunnel-shaped regeneration space constructed in the inside with a fire resistant material and removing a portion of the fixed carbon to obtain recycled carbon fibers.